The engine may start and stall with the security light flashing. This is commonly caused by a failed passlock sensor which is part of the ignition lock cylinder. A secondary cause could be the ignition switch itself. Worn contacts inside the ignition switch can cause voltage drop issues which can affect the passlock system. Proper diagnoses should be performed before replacing any parts.

if my car is parked on a hill and i have to put it in reverse it does a really hard jolt or a kick. while im driving it does it again around 30 mph and again around 60 mph. sometimes if im at a stop light it kind of jerks as i start to take off.

The intake manifold gasket can develop external engine oil or coolant leaks. In some cases the failed gasket will leak coolant internally. The manifold gasket will need to be replaced to correct this issue.

Acid may leak from the battery at the cable connections, resulting in corrosion on the battery cable ends and in the battery tray. A Leaking battery should be replaced and the cables thoroughly cleaned or replaced if necessary.

The transmission pressure control solenoid may fail causing erratic shifting. Our technicians tell us that partial dis-assembly of the transmission is necessary to replace a failed pressure control solenoid.

The steering may develop a clunk type noise from the upper intermediate steering shaft. Our technicians tell us that you should check with your local GM dealer to find out what the latest repair is for this condition.